Exposure apparatus and device manufacturing method having lower scanning speed to expose peripheral shot area

Abstract

An exposure apparatus includes a substrate stage having a substrate holder to hold a substrate, a gap being formed between an edge of the held substrate and a surface surrounding the held substrate, and a controller that controls an exposure operation in which shot areas of the substrate are exposed sequentially and respectively with an image through liquid of a liquid immersion area which covers a portion of an upper surface of the substrate. The controller moves the substrate stage at a first speed to expose one of the shot areas to the image through the liquid, moves the substrate stage at a second speed, that is lower than the first speed, to expose another one of the shot areas to the image through the liquid, and during the exposing of the another one of the shot areas, the liquid immersion area is formed over a portion of the gap.

What is claimed is: 
     
       1. An exposure apparatus comprising:
 a projection optical system having an optical element; 
 a substrate stage having a substrate holder on which a substrate is held, a gap being formed between an edge of the substrate held on the substrate holder and an upper surface of the substrate stage that surrounds the substrate holder, the substrate holder holding the substrate such that an upper surface of the substrate is substantially flush with the upper surface of the substrate stage; 
 a retaining member having a flow path through which a liquid flows and having an opening through which an image is projected from the projection optical system, the retaining member forming a liquid immersion area of the liquid under the projection optical system; and 
 a controller that controls an exposure operation in which a plurality of shot areas of the substrate are exposed sequentially and respectively with the image through the liquid of the liquid immersion area which covers only a portion of the upper surface of the substrate, 
 wherein 
 the controller moves the substrate stage at a first speed to expose one of the shot areas of the substrate to the image through the liquid of the liquid immersion area, 
 the controller moves the substrate stage at a second speed, that is lower than the first speed, to expose another one of the shot areas of the substrate to the image through the liquid of the liquid immersion area, 
 during the exposing of the another one of the shot areas, the liquid immersion area is formed over a portion of the gap, 
 during the exposure of the plurality of shot areas of the substrate, the substrate stage is moved such that a portion of the liquid immersion area is formed on a part of the upper surface of the substrate stage, and 
 during a first time period in which the one of the shot areas is exposed, the controller maintains the scanning speed of the substrate stage at the first speed, and during a second time period in which the another one of the shot areas is exposed, the controller maintains the scanning speed of the substrate stage at the second speed. 
 
     
     
       2. The apparatus according to  claim 1 , wherein:
 the substrate stage has a recessed portion in which the substrate holder is provided, and 
 the upper surface of the substrate stage surrounds the recessed portion. 
 
     
     
       3. The apparatus according to  claim 1 , wherein:
 the substrate stage has a plate portion which surrounds the held substrate, and 
 the upper surface of the substrate stage includes an upper surface of the plate portion. 
 
     
     
       4. The apparatus according to  claim 1 , wherein the liquid is retained under the optical element of the projection optical system, while the liquid immersion area is formed over the portion of the gap between the upper surface of the held substrate and the upper surface of the substrate stage that surrounds the held substrate. 
     
     
       5. The apparatus according to  claim 1 , wherein a size of the gap is from 0.1 mm to 1 mm. 
     
     
       6. The apparatus according to  claim 1 , wherein the shot areas are sequentially and respectively exposed while moving the substrate alternately in first and second directions that are opposite to each other. 
     
     
       7. The apparatus according to  claim 1 , further comprising:
 a supply port; and 
 a recovery port, 
 wherein: 
 the liquid immersion area is formed by performing a liquid supply from the supply port and a liquid recovery from the recovery port, 
 the recovery port is arranged such that the upper surface of the substrate faces the recovery port, and 
 the recovery port collects the liquid along with gas. 
 
     
     
       8. The apparatus according to  claim 7 , wherein:
 the supply port is arranged such that the upper surface of the substrate faces the supply port and such that the supply port surrounds a projection area to which the image is projected, and 
 the recovery port is arranged such that the recovery port surrounds the supply port. 
 
     
     
       9. The apparatus according to  claim 1 , further comprising:
 a supply port; and 
 a recovery port, 
 wherein the liquid immersion area is formed by performing a liquid supply from the supply port and a liquid recovery from the recovery port. 
 
     
     
       10. The apparatus according to  claim 9 , wherein:
 the recovery port is arranged such that the upper surface of the substrate faces the recovery port, 
 the recovery port is arranged such that the recovery port surrounds a projection area to which the image is projected, and 
 the recovery port collects the liquid along with gas. 
 
     
     
       11. The apparatus according to  claim 10 , wherein:
 the supply port is arranged such that the upper surface of the substrate faces the supply port, and 
 the recovery port is arranged such that the recovery port surrounds the supply port. 
 
     
     
       12. The apparatus according to  claim 11 , wherein the supply port is arranged such that the supply port surrounds the projection area. 
     
     
       13. The apparatus according to  claim 9 , wherein:
 the retaining member has the recovery port arranged such that the upper surface of the substrate faces the recovery port and such that the recovery port surrounds a projection area to which the image is projected, and 
 the recovery port collects the liquid along with gas. 
 
     
     
       14. The apparatus according to  claim 13 , wherein the retaining member includes a recovery flow path, the liquid collected from the recovery port flows in the recovery flow path upwardly in a vertical direction, and then flows in the recovery flow path in a horizontal direction. 
     
     
       15. The apparatus according to  claim 13 , wherein:
 the retaining member has the supply port arranged such that the upper surface of the substrate faces the supply port, and 
 the recovery port is provided such that the recovery port surrounds the supply port. 
 
     
     
       16. The apparatus according to  claim 13 , wherein:
 the supply port is arranged such that the supply port surrounds the projection area. 
 
     
     
       17. The apparatus according to  claim 9 , wherein a second gap is formed between a first surface of the optical element and a second surface of the retaining member. 
     
     
       18. The apparatus according to  claim 17 , wherein the first surface is repellent for the liquid. 
     
     
       19. The apparatus according to  claim 17 , wherein the second surface is repellent for the liquid. 
     
     
       20. The apparatus according to  claim 17 , wherein the first surface is located above a lower end surface of the optical element. 
     
     
       21. The apparatus according to  claim 20 , wherein the first surface is arranged such that the first surface intersects with a surface substantially perpendicular to an optical axis of the projection optical system. 
     
     
       22. The apparatus according to  claim 21 , wherein the first surface extends substantially parallel to the optical axis of the projection optical system. 
     
     
       23. The apparatus according to  claim 20 , wherein the optical element has an outer surface which extends upwardly from the lower end surface of the optical element and the outer surface includes the first surface. 
     
     
       24. The apparatus according to  claim 17 , wherein:
 the optical element is held by a holding component, and 
 the holding component is disposed above the retaining member. 
 
     
     
       25. The apparatus according to  claim 17 , wherein:
 the optical element is held by a holding component, and 
 a portion of the holding component is located between a portion of the optical element and a portion of the retaining member. 
 
     
     
       26. The apparatus according to  claim 25 , wherein the portion of the retaining member located under the portion of the holding component is substantially perpendicular to an optical axis of the projection optical system. 
     
     
       27. The apparatus according to  claim 17 , wherein the retaining member is an annular member. 
     
     
       28. The apparatus according to  claim 17 , wherein the retaining member is movable in a direction parallel to an optical axis of the projection optical system. 
     
     
       29. The apparatus according to  claim 9 , further comprising a sensor having a receiver which receives light from the projection optical system through the liquid supplied from the supply port. 
     
     
       30. The apparatus according to  claim 29 , wherein the sensor has a transparent member provided on the substrate stage and the receiver receives the light from the projection optical system through the transparent member. 
     
     
       31. The apparatus according to  claim 9 , further comprising:
 an alignment system; and 
 a reference provided on the substrate stage, 
 wherein the reference is detected by the alignment system through the projection optical system and the liquid supplied from the supply port. 
 
     
     
       32. The apparatus according to  claim 31 , wherein the substrate stage is provided with a reference member having the reference, and the reference is detected by the alignment system through the supplied liquid filled in a space between the projection optical system and the reference member. 
     
     
       33. The apparatus according to  claim 31 , wherein the reference includes a mark. 
     
     
       34. The apparatus according to  claim 1 , wherein the controller moves the substrate stage at the second speed during the exposing of the another shot area such that the liquid of the liquid immersion area is prevented from flowing out. 
     
     
       35. The apparatus according to  claim 1 , wherein the controller moves the substrate stage at the second speed during the exposing of the another shot area such that the liquid of the liquid immersion area is prevented from scattering. 
     
     
       36. The apparatus according to  claim 1 , wherein during the exposing of the one of the shot areas, the liquid immersion area is not formed over any portion of the gap. 
     
     
       37. The apparatus according to  claim 1 , wherein during the exposing of the one of the shot areas, the liquid immersion area is formed only on the upper surface of the substrate. 
     
     
       38. The apparatus according to  claim 1 , wherein during the exposing of the one of the shot areas, an entirety of the liquid immersion area is formed on the upper surface of the substrate. 
     
     
       39. The apparatus according to  claim 1 , wherein the one of the shot areas is located in a central portion of the upper surface of the substrate. 
     
     
       40. The apparatus according to  claim 1 , wherein the another one of the shot areas is located in a peripheral portion of the upper surface of the substrate. 
     
     
       41. The apparatus according to  claim 40 , wherein the another one of the shot areas is smaller than the one of the shot areas. 
     
     
       42. The apparatus according to  claim 1 , wherein pressure change of the liquid of the liquid immersion area is reduced by moving the substrate stage at the second speed that is lower than the first speed. 
     
     
       43. A device manufacturing method comprising:
 exposing a substrate using the apparatus defined in  claim 1 ; and 
 processing the exposed substrate. 
 
     
     
       44. The apparatus according to  claim 1 , wherein the gap extends in a horizontal direction. 
     
     
       45. The apparatus according to  claim 1 , wherein the gap extends horizontally between the edge of the substrate and an adjacent edge of the upper surface of the substrate stage that surrounds the substrate holder. 
     
     
       46. The apparatus according to  claim 1 , wherein at least a portion of the gap extends below the upper surface of the substrate stage that surrounds the held substrate. 
     
     
       47. The apparatus according to  claim 46 , wherein the upper surface of the substrate stage that surrounds the held substrate is configured to maintain the liquid immersion area during exposure of a peripheral portion of the substrate with the image through the liquid of the liquid immersion area. 
     
     
       48. The apparatus according to  claim 46 , wherein the upper surface of the substrate stage that surrounds the held substrate is configured to prevent the liquid of the liquid immersion area from flowing out during exposure of a peripheral portion of the substrate with the image through the liquid of the liquid immersion area. 
     
     
       49. The apparatus according to  claim 1 , wherein
 the retaining member has (i) a lower surface that surrounds the optical element, (ii) the opening formed in and surrounded by the lower surface and through which the image of the pattern is projected from the projection optical system, (iii) a liquid supply port through which the liquid is supplied, and (iv) liquid recovery ports located in the lower surface at least on opposite sides of the opening, and 
 the retaining member forms the liquid immersion area of the liquid under the optical element of the projection optical system by supplying the liquid through the liquid supply port and recovering the liquid through the liquid recovery ports. 
 
     
     
       50. An exposure apparatus comprising:
 a projection optical system having an optical element; 
 a substrate stage having a substrate holder on which a substrate is held and having an upper surface adjacent to and surrounding an upper surface of the held substrate, the substrate holder holding the substrate such that the upper surface of the substrate is substantially flush with the upper surface of the substrate stage; 
 a retaining member having a flow path through which a liquid flows and having an opening through which an image is projected from the projection optical system, the retaining member forming a liquid immersion area of the liquid under the projection optical system; and 
 a controller that controls an exposure operation in which a plurality of shot areas of the substrate are exposed sequentially and respectively with the image through the liquid of the liquid immersion area which covers only a portion of the upper surface of the substrate, 
 wherein 
 the controller moves the substrate stage at a first speed to expose one of the shot areas of the substrate to the image through the liquid of the liquid immersion area, 
 the controller moves the substrate stage at a second speed, that is lower than the first speed, to expose another one of the shot areas of the substrate to the image through the liquid of the liquid immersion area, 
 during the exposing of the another one of the shot areas, the liquid immersion area is formed on a portion of the upper surface of the held substrate and the liquid immersion area is formed on a portion of the upper surface of the substrate stage, and 
 during a first time period in which the one of the shot areas is exposed, the controller maintains the scanning speed of the substrate stage at the first speed, and during a second time period in which the another one of the shot areas is exposed, the controller maintains the scanning speed of the substrate stage at the second speed. 
 
     
     
       51. The apparatus according to  claim 50 , wherein:
 the substrate stage has a recessed portion in which the substrate holder is provided, and 
 the upper surface of the substrate stage surrounds the recessed portion. 
 
     
     
       52. The apparatus according to  claim 50 , wherein:
 the substrate stage has a plate portion which surrounds the held substrate, and 
 the upper surface of the substrate stage includes an upper surface of the plate portion. 
 
     
     
       53. The apparatus according to  claim 50 , wherein the liquid is retained under the projection optical system, while the liquid immersion area is formed on the portion of the upper surface of the substrate stage and the portion of the upper surface of the held substrate. 
     
     
       54. The apparatus according to  claim 50 , wherein the shot areas are sequentially and respectively exposed while moving the substrate alternately in first and second directions that are opposite to each other. 
     
     
       55. The apparatus according to  claim 50 , wherein a gap is formed between the upper surface of the substrate stage and the upper surface of the held substrate, and a size of the gap is from 0.1 mm to 1 mm. 
     
     
       56. The apparatus according to  claim 50 , further comprising:
 a supply port; and 
 a recovery port, 
 wherein: 
 the liquid immersion area is formed by performing a liquid supply from the supply port and a liquid recovery from the recovery port, 
 the recovery port is arranged such that the upper surface of the substrate faces the recovery port, and 
 the recovery port collects the liquid along with gas. 
 
     
     
       57. The apparatus according to  claim 56 , wherein:
 the supply port is arranged such that the upper surface of the substrate faces the supply port and such that the supply port surrounds a projection area to which the image is projected, and 
 the recovery port is arranged such that the recovery port surrounds the supply port. 
 
     
     
       58. The apparatus according to  claim 50 , further comprising:
 a supply port; and 
 a recovery port, 
 wherein the liquid immersion area is formed by performing a liquid supply from the supply port and a liquid recovery from the recovery port. 
 
     
     
       59. The apparatus according to  claim 58 , wherein:
 the recovery port is arranged such that the upper surface of the substrate faces the recovery port, 
 the recovery port is arranged such that the recovery port surrounds a projection area to which the image is projected, and 
 the recovery port collects the liquid along with gas. 
 
     
     
       60. The apparatus according to  claim 59 , wherein:
 the supply port is arranged such that the upper surface of the substrate faces the supply port, and 
 the recovery port is arranged such that the recovery port surrounds the supply port. 
 
     
     
       61. The apparatus according to  claim 60 , wherein the supply port is arranged such that the supply port surrounds the projection area. 
     
     
       62. The apparatus according to  claim 58 , wherein:
 the retaining member has the recovery port arranged such that the upper surface of the substrate faces the recovery port and such that the recovery port surrounds a projection area to which the image is projected, and 
 the recovery port collects the liquid along with gas. 
 
     
     
       63. The apparatus according to  claim 62 , wherein the retaining member includes a recovery flow path, the liquid collected from the recovery port flows in the recovery flow path upwardly in a vertical direction, and then flows in the recovery flow path in a horizontal direction. 
     
     
       64. The apparatus according to  claim 62 , wherein:
 the retaining member has the supply port arranged such that the upper surface of the substrate faces the supply port, and 
 the recovery port is provided such that the recovery port surrounds the supply port. 
 
     
     
       65. The apparatus according to  claim 64 , wherein:
 the supply port is arranged such that the supply port surrounds the projection area. 
 
     
     
       66. The apparatus according to  claim 58 , wherein a second gap is formed between a first surface of the optical element and a second surface of the retaining member. 
     
     
       67. The apparatus according to  claim 66 , wherein the first surface is repellent for the liquid. 
     
     
       68. The apparatus according to  claim 66 , wherein the second surface is repellent for the liquid. 
     
     
       69. The apparatus according to  claim 66 , wherein the first surface is located above a lower end surface of the optical element. 
     
     
       70. The apparatus according to  claim 69 , wherein the first surface intersects with a surface substantially perpendicular to an optical axis of the projection optical system. 
     
     
       71. The apparatus according to  claim 70 , wherein the first surface extends substantially parallel to the optical axis of the projection optical system. 
     
     
       72. The apparatus according to  claim 69 , wherein the optical element has an outer surface which extends upwardly from the lower end surface of the optical element and the outer surface includes the first surface. 
     
     
       73. The apparatus according to  claim 66 , wherein:
 the optical element is held by a holding component, and 
 the holding component is disposed above the retaining member. 
 
     
     
       74. The apparatus according to  claim 66 , wherein:
 the optical element is held by a holding component, and 
 a portion of the holding component is located between a portion of the optical element and a portion of the retaining member. 
 
     
     
       75. The apparatus according to  claim 74 , wherein the portion of the retaining member located under the portion of the holding component is substantially perpendicular to an optical axis of the projection optical system. 
     
     
       76. The apparatus according to  claim 66 , wherein the retaining member is an annular member. 
     
     
       77. The apparatus according to  claim 66 , wherein the retaining member is movable in a direction parallel to an optical axis of the projection optical system. 
     
     
       78. The apparatus according to  claim 58 , further comprising a sensor having a receiver which receives light from the projection optical system through the liquid supplied from the supply port. 
     
     
       79. The apparatus according to  claim 78 , wherein the sensor has a transparent member provided on the substrate stage and the receiver receives the light from the projection optical system through the transparent member. 
     
     
       80. The apparatus according to  claim 58 , further comprising:
 an alignment system; and 
 a reference provided on the substrate stage, 
 wherein the reference is detected by the alignment system through the projection optical system and the liquid supplied from the supply port. 
 
     
     
       81. The apparatus according to  claim 80 , wherein the substrate stage is provided with a reference member having the reference, and the reference is detected by the alignment system through the supplied liquid filled in a space between the projection optical system and the reference member. 
     
     
       82. The apparatus according to  claim 80 , wherein the reference includes a mark. 
     
     
       83. The apparatus according to  claim 50 , wherein during the exposing of the one of the shot areas the liquid immersion area is not formed on the upper surface of the substrate stage. 
     
     
       84. The apparatus according to  claim 50 , wherein during the exposing of the one of the shot areas, the liquid immersion area is formed only on the upper surface of the substrate. 
     
     
       85. The apparatus according to  claim 50 , wherein during the exposing of the one of the shot areas, an entirety of the liquid immersion area is formed on the upper surface of the substrate. 
     
     
       86. The apparatus according to  claim 50 , wherein the one of the shot areas is located in a central portion of the upper surface of the substrate. 
     
     
       87. The apparatus according to  claim 50 , wherein the another one of the shot areas is located in a peripheral portion of the upper surface of the substrate. 
     
     
       88. The apparatus according to  claim 87 , wherein the another one of the shot areas is smaller than the one of the shot areas. 
     
     
       89. The apparatus according to  claim 50 , wherein pressure change of the liquid of the liquid immersion area is reduced by moving the substrate stage at the second speed that is lower than the first speed. 
     
     
       90. A device manufacturing method comprising:
 exposing a substrate using the apparatus defined in  claim 50 ; and 
 processing the exposed substrate. 
 
     
     
       91. The apparatus according to  claim 50 , wherein a gap is formed between the upper surface of the substrate stage and the upper surface of the held substrate. 
     
     
       92. The apparatus according to  claim 91 , wherein the gap extends in a horizontal direction. 
     
     
       93. The apparatus according to  claim 91 , wherein the gap extends horizontally between an edge of the upper surface of the substrate and an adjacent edge of the upper surface of the substrate stage that surrounds the held substrate. 
     
     
       94. The apparatus according to  claim 91 , wherein at least a portion of the gap extends below the upper surface of the substrate stage that surrounds the held substrate. 
     
     
       95. The apparatus according to  claim 94 , wherein the upper surface of the substrate stage that surrounds the held substrate is configured to maintain the liquid immersion area during exposure of a peripheral portion of the substrate with the image through the liquid of the liquid immersion area. 
     
     
       96. The apparatus according to  claim 94 , wherein the upper surface of the substrate stage that surrounds the held substrate is configured to prevent the liquid of the liquid immersion area from flowing out during exposure of a peripheral portion of the substrate with the image through the liquid of the liquid immersion area. 
     
     
       97. The apparatus according to  claim 50 , wherein
 the retaining member has (i) a lower surface that surrounds the optical element, (ii) the opening formed in and surrounded by the lower surface and through which the image of the pattern is projected from the projection optical system, (iii) a liquid supply port through which the liquid is supplied, and (iv) liquid recovery ports located in the lower surface at least on opposite sides of the opening, and 
 the retaining member forms the liquid immersion area of the liquid under the optical element of the projection optical system by supplying the liquid through the liquid supply port and recovering the liquid through the liquid recovery ports.